TM 5-3810-207-20/TO 36C23-3-37-12
Figure 28. Clearance light, removal, disassembly, reassembly, and installation.
Section II. CRANE ENGINE ASSEMBLY
90. General
The six intake and six exhaust valves are located in
the cylinder block on the right side of the engine and are
raised and lowered by tappets in contact with the
camshaft. Adjusting screws in the tappets provide the
means of adjusting the valve clearance. The stem of
each valve rides within a valve guide pressed in the
block. Intake valves control the admission of the fuel-air
mixture to the cylinders, while the exhaust valves permit
the expulsion of exhaust gages from the cylinder. The
engine governor is a centrifugal unit gear-driven from
the camshaft and connected to the carburetor through
adjustable linkage which controls the speed of the
engine.
91. Valve Cover Assembly
a.
Removal. Remove the valve cover assembly
as instructed on figure 29.
b.
Cleaning and Inspection.
(1)
Clean all parts with an approved cleaning
solvent. Remove the old gasket from the valve cover.
(2)
Inspect the valve cover for cracks,
breaks, bends, and other damage. Replace defective
cover and gasket.
(3)
Inspect the bypass tube for cracks,
breaks, and other damage. Replace defective bypass
tube. Replace cover gasket.
c.
Installation. Install the valve cover assembly as
illustrated on figure 29.
92. Valve Adjustment
a.
Remove the valve covers from the engine (par.
91).
b.
Start the engine, allowing it to heat to normal
operating temperature (TM 5-3810-207-10).
c.
Adjust the valves as instructed on figure 30.
d.
Install the valve covers (par. 91).
e.
The compression test is as follows:
(1)
Remove the spark plug (par. 76).
(2)
Place a suitable cylinder compression
tester in the spark plug hole and crank the
engine with the starter.
(3)
The compression gage reading should be
from 80 to 85 psi.
(4)
Install the spark plug (par. 76).
(5)
Test the remaining cylinders in a similar
manner.
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